During normal, recommended unit operation of a utility style steam generator, coal ash is continuously being created and continuously being removed from the bottom of the furnace. Unusual conditions may arise that can prevent continuous ash removal. During these conditions, ash may accumulate and increase the mass of the furnace. Since most furnaces are partially or wholly suspended from above, a large increase in mass can potentially create an overload condition that will rip seams, deform supports or structures, or result in tubing failure within the furnace.
Large ash clumps have been created and fallen down within furnaces causing damage to the furnace. Therefore, it is very desirable to monitor the rate of accumulation of ash and relative increase in suspended mass.
Traditional furnace support systems do not provide a means to let operators know if there is a change in suspended mass. Existing systems employ a visual method where the operator observes ash build-up in a furnace through an observation hole or an observation door. This is only useful where there is a direct line of sight from the observation point to the ash accumulation inside of the furnace.
Currently, there is a need for an accurate method of monitoring the accumulation of ash in a furnace.